Techniques for indicating a specific area on a printed matter with markers have been devised.
For example, Japanese Patent No. 2938338 discusses a two dimension code which is encoded from some data and stuck to a printed matter. A URL (Uniform Resource Locator), for example, is encoded into a two dimension code, and a reader for reading and processing two dimension codes restores original data from the two dimension code. In this case, the reader may find the position of the two dimension code by reading markers arranged at corners of the two dimension code.